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diff --git a/doc/html/UsingIDL.html b/doc/html/UsingIDL.html new file mode 100644 index 0000000..42f2048 --- /dev/null +++ b/doc/html/UsingIDL.html @@ -0,0 +1,154 @@ +<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN"> +<html> + <head> + <title>IEEEIO IDL/PV-Wave Interface</title> + </head> + <body bgcolor="#F0F0F0"> + <table><tr> + <td><img src="Images/info.gif"></td> + <td><h1>IDL/PV-Wave</h1></td> + </tr></table> + <hr> + <h1>Using the IDL/PV-Wave Interface</h1> + The IDL/PV-Wave interface is only for reading. In the future + file writing may be supported, but there hasn't been a need for + this as of yet. The reader is very simplistic right now so you + must convert files to native byte order using the <a + href="Utilities.html#convert2native">convert2native</a> utility + in order for this reader to understand the file. Likewise, + there is support for reading attributes but annotation reading + has been delayed due to lack of interest in the short term.<p> + + The procedures are contained in the file + <a href="src/ieeereader.pro">ieeereader.pro</a>. They can be + read into IDL using the command <code>.run + ieeereader.pro</code>. You can configure this file to + autoload by breaking the routines <code>ieeeopen</code>, + <code>ieeeclose</code>, <code>ieeeread</code>, and + <code>ieeereadattr</code> + into separate files named + <i>procedurename</i><code>.pro</code>.<p> + + <hr> + <UL> + <LI><a href="#Opening">Opening and Closing Datafiles using + <code>ieeeopen</code> and <code>ieeeclose</code></a> + <LI><a href="#Info">Querying the file for the number of + datasets and attributes stored using + <code>ieeendatasets</code> and <code>ieeenattribs</code></a> + <LI><a href="#Reading">Reading Datasets using <code>ieeeread</code></a> + <LI><a href="#ReadAttribs">Reading Attributes using <code>ieeereadattr</code></a> + </UL> + + <hr> + <a name="Opening"><h2>Opening and Closing Files</h2></a> + Like <code>openr</code> you must open a file handle to access + the IEEEIO files in IDL.<p> + <b>IDL Function</b><br> + <code>filedescriptor=ieeeopen('filename.raw')</code><P> + This function opens a file descriptor for reading. Currently + the IDL interface is a read-only interface.<p> + To close an IEEEIO filedescriptor and reclaim its resources you + use <code>ieeeclose</code>.<p> + <b>IDL Procedure</b><br> + <code>ieeeclose,filedescriptor</code> + Closes the filedescriptor. It will also deallocate any existing + IDL handles when I get this thing converted to use dynamic + datastructures.<p> + <hr> + <a name="Info"><h2>Querying File Information</h2></a> + <b>IDL Function</b> + <code>ieeendatasets(descriptor)</code><br> + Returns number of datasets in the file<p> + + <b>IDL Function</b> + <code>ieeenattribs(descriptor,datasetnumber)</code><br> + Returns number of attributes bound to a particular dataset.<p> + + <hr> + <a name="Reading"><h2>Reading Datasets</h2></a> + <b>IDL Procedure</b> + <code>ieeeread,filedescriptor[,datasetnumber]</code> + <DL> + <DT>The <b>datasetnumber</b> defaults to 0 if you don't specify + <DT>Named Params + <UL> + <LI><b>RANK = </b>returns rank of dataset + <LI><b>DIMENSIONS = </b> returns dims (allocates if none specified) + <LI><b>TYPE = </b> Integer datatype...<br> + In terms of IDL datatypes + 0=Byte, 1=Fix, 2=Long,3=<i>not availible in IDL</i>, + 4=Float,5=Double + <LI><b>DATA = </b> Returns data. If storage is provided, + then it will + copy into that storage space. Otherwise it will + allocate. + </UL> + <DT>The following switches affect Data allocation/management + <UL> + <LI><b>/INFO</b> : Makes it skip reading the data + <LI><b>/ASSOC_1D</b> : Associates data as a sequence of 1D x-columns + (eg data=assoc(unit,xarr(dims(0))) + <LI><b>/ASSOC_2D</b> : Associates data as a sequence of 2D xy-slices + <LI><b>/ASSOC_3D</b> : Associates data as a sequence of 3D + blocks of data + (note: only block #0 is valid of course) + <LI><b>/ASSOC_ELEMENTS</b> : Associates data as a sequence of elements + <LI><b>/ALLOCATE</b> : Forces it to nuke any existing data and + allocate + new storage for the data before copying + <LI><b>/COPY</b> : Forces it to copy into preallocated data space. + This will force an error if no data is availible + or if the availible preallocated data space is too + small. + </UL> + </DL> + + <hr> + <a name="ReadAttribs"><h2>Reading Attributes</h2></a> + <b>IDL Procedure</b><br> + <code>ieeereadattr,descriptor,[datasetnumber]</code> + <DL> + <DD><b>datasetnumber</b> defaults to 0 if not specified + <DD>Named parameters are + <UL> + <LI><b>NUMBER =</b>the index of the attribute (ranges from + 0 to nattribs-1)<pr> + nattributes is computed per dataset. + <LI><b>NAME = </b> The name of the attribute. If you + specify a <i>NAME=</i> + without the <i>NUMBER=</i>, it will search for the attribute + based on its name. However, if you specify a number + with <i>NUMBER=</i>, it will retrieve the attribute based + on its index and replace the <i>NAME</i> parameter with + the name of the attrib it read. + <LI><b>LENGTH = </b> number of elements in the attribute + data array + <LI><b>TYPE = </b> datatype of the attribute + <LI><b>DATA = </b> The place to put the attribute data. + If the array + exists and it is the proper size, then it will copy + into the array. Otherwise it will nuke the array + and replace it with a properly sized one. + </UL> + <DD> Data reading is affected by the following flags + <UL> + <LI><b>/ASSOC_ELEMENTS</b> : Associate as an array of elements + <LI><b>/ASSOC_1D</b> : Associate as a 1D array + <LI><b>/COPY</b> : Forces an error if the DATA= you + provided is not the + correct size. + <LI><b>/ALLOCATE</b> : Forces destruction and reallocation + of the array + you provide with <i>DATA=</i> + <LI><b>/INFO</b> : Does not read data. Just for getting info. + </UL> + </DL> + <hr> + <address><a href="mailto:jshalf@suttung.aei-potsdam.mpg.de">John Shalf</a></address> + <!-- Created: Tue Apr 8 18:57:06 MDT 1997 --> + <!-- hhmts start --> +Last modified: Wed Apr 9 11:41:11 MDT +<!-- hhmts end --> + </body> +</html> |